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Abstract Titanium dioxide is a photocatalyst, known not only for its ability to oxidize organic contaminants, but also for its antimicrobial properties. In this article, significant enhancement of the antimicrobial activity of TiO2(up to 32 times) was demonstrated after its activation by ball milling. The antimicrobial activity was analyzed for one fungal and 13 bacterial ATCC strains using the microdilution method and recording the minimum inhibitory concentration (MIC) values. In order to further investigate the correlation between the mechanical activation of TiO2and its antimicrobial activity, the structure, morphology and phase composition of the material were studied by means of Electron Microscopy, X‐ray diffraction and nitrogen adsorption‐desorption measurements. UV‐Vis diffuse reflectance spectra were recorded and the Kubelka‐Munk function was applied to convert reflectance into the equivalent band gap energy (Eg) and, consequently, to investigate changes in theEgvalue. X‐ray photoelectron spectroscopy was used to analyze the influence of mechanical activation on the Ti 2p and O 1s spectra. The presented results are expected to enable the development of more sustainable and effective advanced TiO2‐based materials with antimicrobial properties that could be used in numerous green technology applications.
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Magnesium sulfide powder analyzed by XPS
High-purity niningerite (MgS) was synthesized by BenchChem under vacuum conditions for use in laboratory simulations of solar-ion space weathering of sulfide minerals that are expected to be present on the surface of Mercury. MgS was initially characterized via x-ray photoelectron spectroscopy prior to investigations into the preferential loss of near-surface sulfur in niningerite with 2 keV H2+ irradiation. Survey and high-resolution (Mg 1s, Mg 2p, S 2p) x-ray photoelectron spectra of as-received magnesium sulfide powder (99.9%) are presented, including surface contaminants that originate from exposure to atmosphere (C 1s, O 1s). Minor impurities derived from sample synthesis (Al 2s, Al 2p) and packaging or processing (F 1s) are noted in the survey spectrum.
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- Award ID(s):
- 2009365
- PAR ID:
- 10582799
- Publisher / Repository:
- American Vacuum Society
- Date Published:
- Journal Name:
- Surface Science Spectra
- Volume:
- 32
- Issue:
- 1
- ISSN:
- 1055-5269
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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